Generally, in electronic devices such as smartphones in which various cards (memory cards or SIM cards) are mounted, for convenience of use, the cards are loaded onto a tray for insertion and extraction.
The card trays of the prior art are classified as metal processed trays, e.g. CNC-machined or metal powder injection molded trays, and plastic injection molded trays.
TABLE 1ProcessingCategorymethodMaterialPriceStrengthThicknessSizeMetalCNCAluminumHighMediumThinMediumprocessedmachiningtrayMetalStainlessHighStrongThinSmallinjectionsteelmoldingPlasticInjectionPlasticLowWeakThickLargetraymolding
As shown in Table 1, metal processed trays are expensive, while plastic trays have the disadvantages of being both weak and large.
In particular, in the case of a card tray made of plastic material, because it is weaker than metal materials, the front end part of the card tray, which contacts the ejecting hinge part, can be deformed or damaged by repeated impacts that occur when the tray is pulled from the card socket; in addition, damage may also occur to the plastic parts of the tray due to friction with the metallic parts or parts made of other materials in the insertion/extraction process.
In addition, the occurrence of resin flash after plastic injection molding is a cause of reduced yield, and to eliminate flash, the tray mold structure must be made more complex, causing a problematic reduction in productivity.
(Patent Reference 0001) Korean Registered Patent Gazette No. 10-1460076 (2014.11.20)
(Patent Reference 0002) Korean Registered Patent Gazette No. 10-1468952 (2014.12.04)